In order to manufacture a semiconductor device, various processes such as a film forming process, an etching process, an oxidation process, a diffusion process, an annealing process, a quality modification process and the like are performed on a semiconductor wafer serving as a substrate to be processed. It is required in these processes to improve a throughput and a production yield along with a trend of a miniaturized and highly integrated semiconductor device. In view of the above, there is known a multi-chamber type semiconductor processing equipment capable of successively performing various processes without exposing a wafer to the atmosphere by coupling a plurality of processing chambers for performing a same process or different type processes to one another via a common transfer chamber.
A semiconductor processing equipment of such type has a transfer mechanism including a multi-joint arm transfer robot disposed in the transfer chamber. The transfer mechanism is used for transferring a semiconductor wafer serving as a substrate to be processed between a processing chamber and a receiving vessel (e.g., a receiving vessel having a lid, which is called a FOUP (Front Opening Unified Pod)) for accommodating therein a plurality of wafers in multi-levels. Before the transfer mechanism is used, a so-called teaching operation is performed by a control unit such as a computer or the like for controlling the transfer mechanism. By performing the teaching operation, important positions, e.g., a position for exchanging a wafer and the like, are stored in the control unit as position coordinates.
In order to improve processing uniformity, the transfer mechanism is required to transfer the wafer to the processing chamber with high accuracy. Accordingly, the high accuracy is required in the teaching operation as well as in repetition accuracy of the transfer mechanism and correction function for the transfer shift of the wafer. Along with such requirement, an automatic teaching system using a sensor is being practically used to cope with the limit of the teaching operation using the naked eye. As for the related art, Japanese Patent Laid-open Application No. 2000-127069 discloses therein a method for aligning a transfer position of a transfer system.